def find1(list ,x):
    flag=0
    for i in list:
        if(i==x):
         flag=1
         break
    if(flag):
        print('find')
    else:
        print('no find')
list1=['鲤鱼','草鱼','鲫鱼','鳙鱼','鲈鱼']
x='鳊鱼'
find1(list1,x)

def find2(dict,x):
   flag=0
   for i in dict.keys():
      if(dict[i][0]==x):
         flag=1
         break
   if(flag):
        print('find')
   else:
        print('no find')
dict={'f1':['鲤鱼','杂食性'],'f2':['草鱼','食草性'],'f3':['鲫鱼','温水性'],'f4':['鳙鱼','温水性'],'f5':['黑鱼','肉食性']}
x='鲫鱼'
find2(dict,x)